Structural shape and method of making same



April 28, 1931.

L. S. TRACHSEL STRUCTURAL SHAPE AND METHOD OF MAKING SAME Filed Dec. 1, 1927 L E s H ATTORNEY Patented Apr. 28, 1931 warren STATES PATENT OFFICE LOUIS S. TRACHSEL, OF FRANKLIN, PENNSYLVANIA s'rnncrnaen SHAPE AND Marne]; or MAKING SAME Application filed December The object of this invention is to provide a new tubular, twisted ornamental shape in- *rought iron or steel suitable for structural, architectural and many other industrial purposes, such as electrical" fixtures,

etc.

in the accompanying drawings in which:

Fig. 1 is an end view,

Fig. 3 illustrates the form which this shape has prior to the-operation of twisting.

My improved shape is clearly illustrated 1, 1927. Serial No. 237,007.

tion having two spaced ribs, one of which is formed by; the outside corner of said angle and the other by and atthe meeting point of said edges.

In testimony whereof I affixmy signature.

LOUIS S. TRACHSEL.

Fig. 2 is a side elevation of the shape, and

The clearest and most simple description, 7 of my mproved structural shape is 1n a verging, arcuate form, transversely considered and the edges 2 are caused to converge and to contact closely, whereby, a tubular form of elliptical cross section is formed. i

In case the angle is twisted hot the edges 2 will remain in contact, but if the angle is'twisted, cold'there will be a slight'recoil that will cause said edges to spring apart slightly.

I claim the following:

a twisted tube of elliptical cross section formed'by twisting a structural angle sufficiently to cause the legs of said angle, to

1. A structural steel shape consisting of meet at the edges thereof, the resulting tube i 40 having two spaced ribs, one of which is formed by the outside corner of said angle and the other by and at the junction of said meeting edges.

2. The method of producing a structural shape which consists in, forming a suitable metal by the process of rolling, into a ninety degree angle having equal legs, then twist- 7 ing said angle sufliciently to cause the edges of the legs of said angle to meet and form a tubular structure of elliptical cross sec- 

